markitekt wrote:Does it do a realistic job of materials like grass without having to instance it?

More or less yes. It (somehow, don't ask me the technical details) does not only apply hadows and make a surface "bumpy" like a bump map but actually creates real geometry sticking out of the surface. Think of roof tiles, grass etc. (although displaced grass will never be as "real" as instanced but for mid distance, it is okay).

There are many renderers that can do that (like V-ray) but I only have experience with Thea in this respect. Here is a post over their forum where I used a single colour image (purely for testing reasons) as diffuse and a displacement map. Then there is the resulting roof below:http://www.thearender.com/forum/viewtop ... 261#p34261(Note that I suck at rendering).

Davids90gt wrote:I'm still a bit confused, why is kerkythea free, and what makes all other render programs worth what they sell for?

Well, Kerky is a bit exceptional, that's why it's free. There are ones that's worth the price and there are obviously heavily overpriced renderers.

Guys like Solo and Gaieus are the experts on this stuff, but programs like Twilight at least make it easy for the novice like me to do very nice renderings quickly. There are many presets for setting up materials and lighting quickly which can be somewhat daunting if you don't have a lot of experience with it. Also it has the ability to do HDRI skies which is another feature that seems to be on the checklist. Cost is always a major factor since realistic rendering isn't a major priority for our daily architectural workflow. I am extremely impressed with some of the work I've seen on Solo's web site and I believe he uses several renderers including Thea, Twilight, and others. I'm interested in their opinions on what are good renderers based on what an individuals specific rendering needs are.Mark

Davids90gt wrote:I have been jumping into Kerkythea a little bit. Is there any reasons i shouldn't use Kerkythea?

I find its GI a little weak. But that shouldn't be a concern for you, as you do mostly exteriors. Let's see ... 64 bit, studio app, free render-ready tree models, instancing brush, free ready-to-use materials, helpful community, some good free tutorials, biased and unbiased rendering. Might be just the app for a beginner with your needs. Caveat: you won't get great results straight away. Don't be put off -learning to make a decent render takes a bit of practice, regardless of the app you're using.

TomDC wrote:So, what you may want to do, is set up mats and lighting in SU using Twilight, then export, and add render-ready trees from the KT site in KT.

Exactly, if you really need those high poly plants. I can often get away with billboards inside Twilight though. And as long as SU can handle them, Twilight has no more issues rendering component instances than Kerky. Also it can render stuff on hidden layers (what a Godsend!)

I use Thea at work (architecture office) and Kerkythea at home (free). They both work very well/easily with sketchup and either would work just fine for you. If you don't mind paying a bit Thea is the better program (no surprise) but you might not need it.

There are plenty of differences between the two (active development not least) but the two main items I notice switching between the two are displacement and layers. Of these, layers is BY FAR the more important. Displacement is nice, and occasionally I do use it, but it depends on the type of result you're looking for.Professionally, the images I'm trying to get are meant to show a compelling presentation of the proposed design to the city or a client. Reasonably believable materials and colors are important, as are good shadows (especially to show depth). Either program will do that just fine. Displacement makes for longer render times and more setup. Plus, if they're overdone they look as bad as if they weren't used at all. There are some real artists who use it in their renderings but are you showing closeups that honestly necessitate that detail (possibly) and do you want to spend the extra time required? For me it's rarely worth the time.

I tend to like "pretty good" renderings, that specifically establish the desired/required lighting and shadows, and then finish in post-pro (these are some great tutorials for that). It's faster and gives you good looking results, even if it's not PR.

About layers. When models start getting very large (usually when doing detailed exterior scenes) it's really nice to be able to turn off some variation of: the grass, the cars, the trees, the people, etc. It's such a basic feature but unless I've missed it you can't do that with Kerkythea. Instead of displacing grass, I usually either use instances (very easy to do in either program) or post-pro as in the tutorial listed above.

Basically, get Thea if the expense makes sense for your business. Since you're just getting it, I imagine you've been doing fine without it in the past and this is just a new (very helpful) area. If that's the case, kerkythea is the way to go; if it works well then upgrade and the workflow if very similar.

Well, Kerkythea xml files can be opened in Thea. So a Kerkythea xml file exported from Twilight after some material tweaks, can also be opened and although the material system is somewhat different, much of the settings get through and you need to tweak less in Thea.

This is of course not the "normal" way of doing it as the dedicated Thea exporter has a bunch of functionalities that the Twilight to Kerky exporter does not have (export model hierarchy for instance). But for a quick and dirty job, it works.

Davids90gt wrote:Thanks for the input! I'm still a bit confused, why is kerkythea free, and what makes all other render programs worth what they sell for?

Kerkythea was born from enthusiasm and with active community it did grow in a point when entering into the commercial arena was only feasible option for further development. Even with a new born Thea Render, Kerkythea did stay free and is still been developed (but in slow cycles).

TomDC wrote:Oh: don't choose a renderer over another because it does displacement. It's a nice feature and all, but it's terribly slow -in any app. And as Gai says, displaced grass doesn't look good.

Indeed! For grass I'd use instancing or/and post pro. I rarely seen good enough grass made with displacement (specially when comparing the added render time). Gravel, pavement, stone walls, water... those are good targets for displacement.

pbacot wrote:And can the same be said of Thea?

Like said before, Thea can import kerkythea xml (be it created by Twilight or Kerkythea). Material systems are different, although some similarities can be find. Thea does a KT material conversion with some heuristics, so little fine-tuning may be in need in case of complex materials. Exporting materials/models from Thea to Kerkythea is not possible.